What Are Claude Code Skills? The Complete Guide with Examples
Learn what Claude Code skills are, how to install them, where to find the best ones, and how to create your own. Covers SKILL.md format, slash commands, and the skills marketplace.
William Wang — Founder of TokRepo & GEOScore AI. Building tools for AI developer productivity and search visibility.
Learn what Claude Code skills are, how they work under the hood, and how to install your first skill in under 60 seconds. This guide covers the SKILL.md standard, skill directories, installation methods, and where to find 500+ community skills.
Prerequisites
- Claude Code installed (CLI, VS Code extension, or desktop app)
- A project directory to test skills in
- Basic terminal/command line knowledge
What Is a Claude Code Skill?
A Claude Code skill is a markdown instruction file that teaches Claude Code how to perform a specific task. When you invoke a skill (via /skill-name), Claude reads the markdown file and follows its instructions — no code compilation, no API integration, just structured text.
# Example: code-reviewer.md
Review the current git diff for:
- Security vulnerabilities (OWASP Top 10)
- Performance regressions
- Missing error handling
- Breaking API changes
Output a structured report with severity ratings.
That's it. Save this as a .md file in the right directory, and Claude Code gains a new capability.
Skills vs MCP Servers vs Rules
| Feature | Skills | MCP Servers | Rules (CLAUDE.md) |
|---|---|---|---|
| Format | Markdown files | Running processes | Markdown file |
| Activation | Slash command (/skill) | Always available | Always active |
| Complexity | Low (write markdown) | High (write code) | Low (write markdown) |
| Use case | Task-specific workflows | External tool access | Project-wide conventions |
| Examples | Code review, deployment, testing | Database, browser, GitHub | Coding standards, patterns |
For a deeper comparison, read Skills vs MCP vs Rules.
How to Install Skills
Method 1: Drop a File (Fastest)
# Project-level skill (available in this project only)
mkdir -p .claude/skills
curl -o .claude/skills/code-reviewer.md https://example.com/skill.md
# Global skill (available in all projects)
mkdir -p ~/.claude/skills
cp code-reviewer.md ~/.claude/skills/
Method 2: Plugin Marketplace
# Install a skill pack from the marketplace
/plugin marketplace add https://github.com/org/skill-pack
/plugin install skill-pack@skill-pack
Method 3: One-Command Install from TokRepo
Every skill on TokRepo includes a copy-paste install command:
# Example: Install the GSD workflow skill
mkdir -p .claude/skills && curl -o .claude/skills/gsd.md \
"https://tokrepo.com/api/v1/tokenboard/raw/ASSET_UUID"
Where Skills Live
| Location | Scope | Priority |
|---|---|---|
.claude/skills/ (project) | Current project only | Highest |
~/.claude/skills/ (global) | All projects | Lower |
| Plugin-installed | Depends on plugin config | Varies |
10 Most Popular Claude Code Skills in 2026
Based on community usage and TokRepo rankings:
- Code Reviewer — Adversarial code review with severity ratings
- GSD Workflow — Plan, execute, and verify development tasks
- Frontend Design — Generate production-grade UI with design principles
- Commit Message Writer — Structured commits following conventions
- Test Generator — Auto-generate unit and integration tests
- PR Creator — Create well-structured pull requests
- Deployment Pipeline — Automated build and deploy workflows
- Documentation Writer — Generate docs from code
- Prompt Architect — Transform vague prompts into expert-level ones
- Refactoring Specialist — Safe, incremental code refactoring
Browse the full collection: Top 500+ Agent Skills on TokRepo.
How to Create Your Own Skill
Step 1: Create the File
touch .claude/skills/my-skill.md
Step 2: Write the Instructions
# My Custom Skill
## When to Use
Activate when the user asks to [describe trigger].
## Instructions
1. First, read the relevant files using...
2. Then, analyze the code for...
3. Finally, output a report with...
## Output Format
- Use markdown tables for structured data
- Include code blocks with language tags
- End with actionable next steps
## Constraints
- Never modify files without confirmation
- Always explain reasoning before changes
- Keep responses under 500 words
Step 3: Test It
# Start Claude Code in your project
claude
# Invoke your skill
/my-skill
Step 4: Share It
Upload your skill to TokRepo to share with the community. Read the full tutorial: How to Create Your First Agent Skill.
Skill Design Best Practices
Do
- Be specific — "Review Python code for SQLAlchemy N+1 query patterns" beats "Review code"
- Include examples — Show input/output examples so Claude understands the expected format
- Set constraints — Define what the skill should NOT do
- Test with edge cases — Try the skill on unusual inputs before sharing
Don't
- Don't be vague — "Make the code better" produces inconsistent results
- Don't overload — One skill, one task. Split complex workflows into multiple skills
- Don't hardcode paths — Use relative paths or let Claude discover the project structure
Cross-Platform Compatibility
The SKILL.md format works across multiple AI coding tools:
| Tool | Skill Location | Format |
|---|---|---|
| Claude Code | .claude/skills/*.md | SKILL.md |
| OpenAI Codex CLI | AGENTS.md | Similar markdown |
| Gemini CLI | GEMINI.md | Similar markdown |
| Cursor | .cursorrules | Text rules |
Most skills on TokRepo can be adapted for any of these tools with minor format changes.
FAQ
Q: What are Claude Code skills? A: Markdown instruction files that teach Claude Code how to perform specific tasks. They're invoked via slash commands and require no coding — just structured text describing what Claude should do.
Q: Are Claude Code skills free? A: Yes. Skills are open markdown files. TokRepo hosts 500+ free community skills that you can install with one command.
Q: How many skills can I install?
A: There's no hard limit. Claude Code loads skills from .claude/skills/ and ~/.claude/skills/. However, each skill adds to the context window, so keep your active skills focused on what you need.
Q: Do skills work offline? A: Skills themselves are local markdown files, but Claude Code requires an internet connection to the Anthropic API. The skill instructions are read locally.
Next Steps
- Browse 500+ skills on TokRepo — install your first skill now
- How to Create Your First Agent Skill — step-by-step tutorial
- Skills vs MCP vs Rules — choose the right extension model
- Best MCP Servers for Claude Code — extend Claude with external tools
- Agent Skills for Teams — standardize skills across your team